The problem of numerical modeling and optimization of wave processes on the basis of a parabolic Schrodinger-type wave equation with a complex non-self-adjoint operator is considered. An optimality criterion is formulated. Properties of an extremal problem are investigated. A numerical method is proposed for the modeling and optimization of acoustic fields in inhomogeneous domains with piecewise continuous parameters.The urgency of development of methods for the mathematical modeling of processes of propagation of acoustic waves in inhomogeneous underwater waveguides is mainly explained by needs for remote sensing and acoustic monitoring of regions of the World Ocean [1-4]. Sound waves are used practically in all types of signalling, communication, location, and remote investigations of the body of water and the bottom of the Ocean. Of significant interest are also questions of formation of acoustic fields with prescribed properties and investigations of distinctive features of propagation of sound waves in inhomogeneous waveguides with allowance for absorption in a medium.From the mathematical viewpoint, the calculation of harmonic sound fields is reduced to the solution of boundary problems for Helmholtz's wave elliptic equation with a complex non-self-adjoint operator in unbounded inhomogeneous domains. At present, many numerical-analytical methods and computational algorithms are developed to solve direct or extremal problems for Helmholtz's equation in homogeneous and nonuniform stratified media [1-2, 5-9]. Difficulties of mathematical investigation of such problems can be overcome using the methodology of approximation of the Helmholtz equation by parabolic Schr && odinger-type equations [3][4][5][10][11][12][13][14]. This allows one to reduce the solution of boundary problems to the solution of the Cauchy problem for wave equations of parabolic type with a complex non-self-adjoint operator, which leads to the necessity of development of efficient numerical methods for the solution of the corresponding approximation problems.In the present article, questions of numerical modeling and optimization of acoustic processes are investigated on the basis of a parabolic wave equation in an inhomogeneous underwater waveguide with piecewise continuous acoustic parameters and with allowance for absorption. A numerical method is proposed for the solution of the direct problem and optimization problems, differential properties of a quality functional are studied, and the stability of the difference scheme is investigated for the direct and conjugate boundary problems with a complex non-self-adjoint operator.